Albert Barnes Commentary Isaiah 56:11

"Yea, the dogs are greedy, they can never have enough; and these are shepherds that cannot understand: they have all turned to their own way, each one to his gain, from every quarter." — Isaiah 56:11 (ASV)

Yes, they are greedy dogs—Margin, ‘Strong of appetite.’ Literally, ‘Strong of soul’ (עזי־נפשׁ ‛azēy-nephesh). Jerome renders it Canes impudentissimi. So the Septuagint, Κύνες ἀναιδεῖς τῇ ψυχῇ Kunes anaideis tē psuchē—‘Dogs impudent in soul.’

They were greedy and insatiable in what the soul or appetite demands.

The idea here is that the prophets referred to here were sensual and disposed to gorge themselves, living only for carnal indulgence, insensible to the rights of others, and never satisfied.

And they are shepherds that cannot understand—They are ignorant of the people's needs and cannot be made to comprehend what those needs are .

They all look to their own way—That is, they are all selfish. The ministers of religion are set apart not to promote their own interests but the welfare and salvation of others.

Every one for his gain—For his own private ends and emoluments.

From his quarter—Lowth states, ‘From the highest to the lowest.’ So Rosenmuller. The Septuagint, Κατὰ τὸ ἑαυτοῦ Kata to heautou—‘Each one according to his own purpose.’

The Hebrew phrase is literally, ‘From his end,’ or extremity. For example, in Genesis 19:4, the term מקצה (mı̂qqâtseh) means ‘From every quarter’; that is, from one end to the other—one and all, the whole.

This seems to be the idea here: that one and all were given to selfishness, to covetousness, and to indulgence in luxury and sensuality.